Finally!! My mechanic friend received the upper spring jounces for my 2008 HHR. I will help him install Monday, Dec.8.
Just wanted to add: many thanks for helping me get the correct parts.
The two that I received had part numbers molded into the plastic base: 25993736 = Black (like the ones I received) and 25993737 = Blue (same mold used for two different materials). And, the plastic bag had the number: GM# 19352221 The off white jounce had these numbers: BASF92>PUR< G0042-KR122-3P (couldn't find these numbers on line).
I love it when things come together like this.

If only I could lay my hands on the coil spring lower seats (many hours surfing the internet - none to be found). I hope the are good enough to reuse, though I will be measuring them for possible 'homemade' versions.
Many thanks again ....
p.s. I ordered a second set of uppers for my 2007 since they may go bad too. On order for several weeks - supposedly on the way.

Success! New upper jounce assemblies installed. And, the lower spring seats both looked in very good shape - got lucky there. The installation was surprisingly easy (with a two post lift).
Tried to attach photos - not sure how to do it ...

 

Great news! Keep it clean and drive it often!

 

Update on my 2008 LS - front end noise started happening, a sound that was like metal scraping when going over bumps (particularly when vehicle weight was reduced on the springs after going over a bump). I had the front struts replaced ($!) and the noise persisted. I turns out the the new bushings I had replaced on the sway bar were causing the noise. A little white lithium grease on the bushing and the noise when away except for a slight squeak once in a great while over bumps. I'm guessing that the new bushings need to 'wear in' a little. Anyway, I thought I'd mention this to those that might hear a scraping type of noise from up front.
Also, I'm still searching for rear coil spring seat 25993738 ... contacting junk yards ... no luck yet. I am determined to make my own from polyurethane if I could get dimensions (even from a damaged used example).
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The swaybar bushings should be installed dry, clean the swaybar to get all the grit off. White lithium grease won’t hurt the bushings but it will dry out and that noise will return.
just saying from experience of owning and driving an HHR for over 16 years and a total of more than 500,000 miles.

 

Thanks, I'll take care of that cleaning when the noise starts to return. At least the temporary lubrication helped to pinpoint the source of the noise.

 

Quick update - sure enough, the noise returned. What is a little strange is that the noise stopped when the ambient temperature was over 50 F and then returned when the temp fell below 40 F. I'm guessing that the colder bushing temperature may make the bushings stiffer (?). Anyway, running without issues now.

 

Cold weather noise is something we have to live with, trust me it’s torture for someone like me who has to know what that noise is and fix it! OCD isn’t just for kids! But after 16 years and over 750,000 miles of driving an HHR , it’s getting better and I recognize the squeaky, rattling noises of the 4 seasons and in the warmer weather, silence is golden!